EP0520789B1 - Videokoder und Kodierungsverfahren - Google Patents

Videokoder und Kodierungsverfahren Download PDF

Info

Publication number
EP0520789B1
EP0520789B1 EP19920305851 EP92305851A EP0520789B1 EP 0520789 B1 EP0520789 B1 EP 0520789B1 EP 19920305851 EP19920305851 EP 19920305851 EP 92305851 A EP92305851 A EP 92305851A EP 0520789 B1 EP0520789 B1 EP 0520789B1
Authority
EP
European Patent Office
Prior art keywords
video data
coding
coding parameter
quantizing
predictive
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
EP19920305851
Other languages
English (en)
French (fr)
Other versions
EP0520789A2 (de
EP0520789A3 (en
Inventor
Yasushi c/o Patents Div. Fujinami
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Sony Corp
Original Assignee
Sony Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Sony Corp filed Critical Sony Corp
Publication of EP0520789A2 publication Critical patent/EP0520789A2/de
Publication of EP0520789A3 publication Critical patent/EP0520789A3/en
Application granted granted Critical
Publication of EP0520789B1 publication Critical patent/EP0520789B1/de
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
    • G06T9/00—Image coding
    • G06T9/008—Vector quantisation
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N19/00—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals
    • H04N19/10—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding
    • H04N19/102—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the element, parameter or selection affected or controlled by the adaptive coding
    • H04N19/103—Selection of coding mode or of prediction mode
    • H04N19/114—Adapting the group of pictures [GOP] structure, e.g. number of B-frames between two anchor frames
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N19/00—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals
    • H04N19/10—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding
    • H04N19/102—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the element, parameter or selection affected or controlled by the adaptive coding
    • H04N19/124—Quantisation
    • H04N19/126—Details of normalisation or weighting functions, e.g. normalisation matrices or variable uniform quantisers
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N19/00—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals
    • H04N19/10—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding
    • H04N19/134—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the element, parameter or criterion affecting or controlling the adaptive coding
    • H04N19/142—Detection of scene cut or scene change
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N19/00—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals
    • H04N19/10—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding
    • H04N19/134—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the element, parameter or criterion affecting or controlling the adaptive coding
    • H04N19/162—User input
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N19/00—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals
    • H04N19/10—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding
    • H04N19/169—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the coding unit, i.e. the structural portion or semantic portion of the video signal being the object or the subject of the adaptive coding
    • H04N19/177—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the coding unit, i.e. the structural portion or semantic portion of the video signal being the object or the subject of the adaptive coding the unit being a group of pictures [GOP]
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N19/00—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals
    • H04N19/10—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding
    • H04N19/169—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the coding unit, i.e. the structural portion or semantic portion of the video signal being the object or the subject of the adaptive coding
    • H04N19/179—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the coding unit, i.e. the structural portion or semantic portion of the video signal being the object or the subject of the adaptive coding the unit being a scene or a shot
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N19/00—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals
    • H04N19/10—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding
    • H04N19/189—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the adaptation method, adaptation tool or adaptation type used for the adaptive coding
    • H04N19/192—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the adaptation method, adaptation tool or adaptation type used for the adaptive coding the adaptation method, adaptation tool or adaptation type being iterative or recursive
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N19/00—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals
    • H04N19/46—Embedding additional information in the video signal during the compression process
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N19/00—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals
    • H04N19/60—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using transform coding
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N19/00—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals
    • H04N19/60—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using transform coding
    • H04N19/61—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using transform coding in combination with predictive coding
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N19/00—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals
    • H04N19/80—Details of filtering operations specially adapted for video compression, e.g. for pixel interpolation
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N19/00—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals
    • H04N19/85—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using pre-processing or post-processing specially adapted for video compression
    • H04N19/87—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using pre-processing or post-processing specially adapted for video compression involving scene cut or scene change detection in combination with video compression
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N5/00—Details of television systems
    • H04N5/76—Television signal recording
    • H04N5/91—Television signal processing therefor
    • H04N5/92—Transformation of the television signal for recording, e.g. modulation, frequency changing; Inverse transformation for playback
    • H04N5/926—Transformation of the television signal for recording, e.g. modulation, frequency changing; Inverse transformation for playback by pulse code modulation
    • H04N5/9261—Transformation of the television signal for recording, e.g. modulation, frequency changing; Inverse transformation for playback by pulse code modulation involving data reduction
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N5/00—Details of television systems
    • H04N5/76—Television signal recording
    • H04N5/91—Television signal processing therefor
    • H04N5/92—Transformation of the television signal for recording, e.g. modulation, frequency changing; Inverse transformation for playback
    • H04N5/926—Transformation of the television signal for recording, e.g. modulation, frequency changing; Inverse transformation for playback by pulse code modulation
    • H04N5/9261—Transformation of the television signal for recording, e.g. modulation, frequency changing; Inverse transformation for playback by pulse code modulation involving data reduction
    • H04N5/9262—Transformation of the television signal for recording, e.g. modulation, frequency changing; Inverse transformation for playback by pulse code modulation involving data reduction using predictive coding
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N5/00—Details of television systems
    • H04N5/76—Television signal recording
    • H04N5/91—Television signal processing therefor
    • H04N5/92—Transformation of the television signal for recording, e.g. modulation, frequency changing; Inverse transformation for playback
    • H04N5/926—Transformation of the television signal for recording, e.g. modulation, frequency changing; Inverse transformation for playback by pulse code modulation
    • H04N5/9261—Transformation of the television signal for recording, e.g. modulation, frequency changing; Inverse transformation for playback by pulse code modulation involving data reduction
    • H04N5/9264—Transformation of the television signal for recording, e.g. modulation, frequency changing; Inverse transformation for playback by pulse code modulation involving data reduction using transform coding
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N9/00—Details of colour television systems
    • H04N9/79—Processing of colour television signals in connection with recording
    • H04N9/80—Transformation of the television signal for recording, e.g. modulation, frequency changing; Inverse transformation for playback
    • H04N9/804—Transformation of the television signal for recording, e.g. modulation, frequency changing; Inverse transformation for playback involving pulse code modulation of the colour picture signal components
    • H04N9/8042—Transformation of the television signal for recording, e.g. modulation, frequency changing; Inverse transformation for playback involving pulse code modulation of the colour picture signal components involving data reduction
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N19/00—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals
    • H04N19/10—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding
    • H04N19/102—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the element, parameter or selection affected or controlled by the adaptive coding
    • H04N19/124—Quantisation
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N19/00—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals
    • H04N19/10—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding
    • H04N19/134—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the element, parameter or criterion affecting or controlling the adaptive coding
    • H04N19/146—Data rate or code amount at the encoder output
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N5/00—Details of television systems
    • H04N5/14—Picture signal circuitry for video frequency region
    • H04N5/147—Scene change detection

Definitions

  • This invention relates to video coders and coding methods.
  • the amount of video data required to define a moving image is very large compared with that required to define audio information. This makes compression of video data prior to recording on a record medium a desirable step.
  • Patent Abstracts of Japan, Vol. 15, No 265 (E-1086) and JP-A-3 088 489 disclose a system in which the required variation of the quantization step width for one block is determined and then fed back to control the coding of a subsequent block.
  • EP-A-0,444,918 discloses a method of compressing image data in which original image data is quantised with an initial first quantisation step, a new quantisation step is then calculated from the calculated image data and the original image data are again quantised with this new quantisation step.
  • a video coder for compressing the data amount of input video data and encoding said input video data, the video coder comprising:
  • a video coding method for compressing the amount of input video data and recording said input video data comprising the steps of:
  • a digital video tape recorder (DVTR) 1 reproduces video data and supplies the video data thus played back to a motion detector circuit 2 and an encoder 3. Also, the DVTR 1 supplies a time code corresponding to the reproduced data to a controller 4.
  • the motion detector circuit 2 operates to detect the motion of a corresponding moving image from the video data input thereto and supplies a signal corresponding to a detected result thereof to the controller 4 and a parameter memory 5.
  • the controller 4 calculates parameters, and supplies the parameters thus calculated to the parameter memory 5, in which they are stored.
  • Various parameters stored in the parameter memory 5 are supplied to the encoder 3 and the motion detector circuit 2.
  • Video data processed by the encoder 3 are supplied to apparatus, not shown, as a bit stream, and are also supplied to a video monitor 6, and are thereby displayed on a picture screen of the video monitor 6.
  • the encoder 3 comprises a frame memory 11 which stores video data, a motion compensator circuit 12 which calculates a difference by using a motion vector, which is known as 'motion compensation', a discrete cosine transform (DCT) circuit 13 for processing data in a DCT fashion, a quantizer circuit 14 for quantizing data output from the DCT circuit 13, a variable length coder circuit 15 which converts the data quantized by the quantizer circuit 14 into a variable length code, an inverse quantizer circuit 16 for inverse-quantizing the data quantized by the quantizer circuit 14 and an inverse DCT circuit 17 for processing the data thus inverse-quantized by the inverse quantizer 16 in an inverse quantizing fashion.
  • DCT discrete cosine transform
  • the DVTR 1 plays back video data from a video tape (not shown) and supplies the reproduced video data to the motion detector circuit 2.
  • the motion detector circuit 2 operates to detect the change of scenes in accordance with the flowchart of Figure 2.
  • the motion detector circuit 2 stores data of one frame input thereto from the DVTR 1 in a motion detecting frame memory housed therein in step S1.
  • the image of the next frame is similarly stored in a motion detecting frame memory housed in the motion detector circuit 2.
  • a motion vector is calculated from video data of two succeeding frames. Image data are divided into blocks of a predetermined size (for example, 8x8 pixels) and the motion vector is detected at every block. The motion vector thus obtained is supplied to and stored in the parameter memory 5.
  • the motion detector circuit 2 calculates one frame of a residual information (absolute difference sum or square sum of data predicted by the resultant motion vector and present data) and outputs a calculated result to the controller 4 in step S4.
  • the controller 4 compares the residual information input from the motion detector circuit 2 with a predetermined threshold level previously set. If the residual information is smaller than or equal to the threshold level as represented by a NO at decision step S5, then the processing proceeds to step S6, whereat it is determined that the scene is not changed and this information is stored in the motion detection frame memory (not shown). If on the other hand the residual is larger than the threshold level as represented by a YES in decision step S5, then the processing proceeds to step S7, whereat it is determined that the scene has changed.
  • the controller 4 stores the information concerning the change of scene in the memory housed therein. Similar processing is repeated until video data are thoroughly processed (in decision step S8). In this way, the controller 4 judges the frame structure of the input video data, and transfers and stores the frame structure thus determined in the parameter memory 5.
  • the I picture uses only a closed information within one picture thereof when encoded and is needed to effect random access and high speed playback.
  • the P picture forward predictive-coded picture
  • the more efficient one of the coding process for coding a difference between a picture and a predictive picture whose motion is compensated (inter-coding process) and coding process for coding a picture without calculating a difference (intra-coded process) is selected at the units of macro-block (for example, 16 x 16 pixels) as the predictive mode.
  • the B picture uses as a predictive picture three kinds of the preceding and already-decoded I picture or P picture, the succeeding and already-decoded I picture or P picture or the interpolated picture formed by the former two kinds of pictures.
  • an amount of data concerning an afterimage of a moving object for example, can be compressed.
  • the most efficient one of the inter-coded and intra-coded processes is selected at the units of the macro block as the predictive mode.
  • Figure 4 shows a table of predictive modes that can be selected at the units of macro-block relative to respective frame structures.
  • the frame structure indicates the kinds of frames composed of the I picture, the P picture and B picture.
  • the sequential order of the frame structure is generally determined in such a pre-determined sequence as to dispose, for example, one P picture between two I pictures and to dispose two B pictures between an I picture and a P picture or the like.
  • the above-mentioned sequence is not always kept and some suitable processing such as to select the frame structure of the picture as the I picture is necessary.
  • This frame structure is read out from the parameter memory 5 and supplied to the motion detector circuit 2 and is thereby used to calculate a motion vector. Further, this frame structure is also supplied to the motion compensator circuit 12 in the encoder 3 and used to calculate a motion compensation amount, as will be described later.
  • the motion detector circuit 2 calculates a mean value of pixels and an absolute residual (absolute value difference or square sum) of respective pixels in respective macro-blocks and outputs the same to the controller 4 as an intra-coded picture residual.
  • the controller 4 operates to determine the predictive mode of each macro-block on the basis of the already-determined frame structure, the residual and the intra-coded picture residual calculated by the motion detector circuit 2 when the change of scene is detected.
  • the predictive mode is used to set a reference picture that is used by the motion compensator circuit 12 in the encoder 3 to calculate the difference.
  • One of four modes that is, intra-coded picture mode, forward predictive-coded picture mode, backward predictive-coded picture mode and bidirectionally predictive-coded picture mode is selected as the predictive mode.
  • the predictive mode is determined is accordance with a flowchart forming Figure 5, for example.
  • step S11 it is determined in decision step S11 by the controller 4 whether or not the frame structure is designated as the I picture. If the frame structure is designated as the I picture as represented by a YES at decision step S11, then the processing proceeds to step S12, whereat the intra-coded picture mode is designated as the predictive mode. If the frame structure is not designated as the I picture as represented by a NO at decision step S11. then the processing proceeds to the next decision step S13. In decision step S13, it is determined whether or not the P picture is designated as the frame structure.
  • step S13 If the P picture is designated as the frame structure as represented by a YES at decision step S13, then the processing proceeds to the next decision step S14, whereat the residual calculated by the motion detector circuit 2 and the intra-coded picture residual are compared with each other. If the intra-coded picture residual is larger than the residual as represented by a YES at decision step S14, then the processing proceeds to step S15.
  • step S15 the forward predictive mode is designated as the predictive mode because it is considered that the encoding efficiency can be improved more if the difference is coded by using the predictive mode.
  • step S16 the intra-coded picture mode is designated as the predictive mode because it is considered that the encoding efficiency can be improved by using the intra-frame coding.
  • step S17 one of three modes of forward predictive-coded picture mode, backward predictive-coded picture mode and bidirectionally predictive-coded picture mode and whose residual becomes minimum is assumed to be a predictive mode.
  • step S18 it is determined whether or not the minimum residual is larger than the intra-coded picture residual. If the minimum residual is larger than the intra-coded picture residual as represented by a YES at decision step S18, then the processing proceeds to step S19, whereat the predictive mode is designated as the intra-coded picture mode because the intra-frame coding can improve the coding efficiency more. If the minimum residual is smaller than the residual within the picture as represented by a NO at decision step S18, then the processing returns to step S17.
  • the controller 4 supplies the predictive mode parameter thus determined to the parameter memory 5, in which it is stored.
  • This predictive mode parameter is supplied to the motion compensator circuit 12 to be used.
  • the motion compensator circuit 12 When the intra-coded picture mode is designated as the frame structure, the motion compensator circuit 12 outputs the input image data as it is. At that time, the motion vector is not supplied to the motion compensator circuit 12 or it can be neglected.
  • the motion compensator circuit 12 extracts a predictive picture from the forward predictive frame stored in the frame memory 11 by utilizing the motion vector supplied thereto and calculates and outputs a difference between the predictive picture and input picture data.
  • the motion compensator circuit 12 extracts a predictive image from the backward predictive frame stored in the frame memory 11 by utilizing the motion vector supplied thereto.
  • the motion compensator circuit 12 extracts the forward predictive picture from the forward predictive frame stored in the frame memory 11 by utilizing two motion vectors of the forward and rearward predictive pictures. Further, the motion compensator 12 extracts the predictive picture from the rearward predictive frame and averages the thus extracted forward and rearward predictive pictures to provide a predictive picture and calculates and outputs a difference between the predictive picture and the input picture data.
  • step S21 the controller 4 estimates the features of respective frames from the residual calculated by the motion detector circuit 2 when the change of scene is detected, thereby determining the quantizing parameter.
  • the quantizing parameter is used to set a quantization step size of the quantizer circuit 14 in the encoder 3. To be more specific, this quantizing parameter is used as a divisor when data output from the DCT circuit 13, for example, are divided by a predetermined value.
  • the controller 4 supplies the quantizing parameter thus determined to the parameter memory 5, in which it is stored.
  • This quantizing parameter is supplied from the parameter memory 5 to the quantizer circuit 14 and determines the quantization step size of the quantizer circuit 14.
  • the encoder 3 operates to encode the video data supplied thereto from the DVTR 1 in response to the motion vector, the frame structure, the predictive mode and the quantizing parameter supplied thereto from the parameter memory 5. Then, the encoder 3 outputs resultant encode data (bit rate and S/N ratio) to the controller 4 in step S22.
  • the controller 4 examines the resultant bit number, the S/N ratio or the like supplied thereto from the encoder 3 and sets a parameter of a defective frame one more time in step S23. That is, if the resultant bit number cannot be reduced sufficiently (that is, the amount of data cannot be compressed sufficiently) or a satisfactory S/N ratio cannot be obtained, then the parameter thus set is regarded as an invalid one and a parameter is set one more time.
  • next step S24 the encoder 3 encodes again the video data in accordance with the parameter thus set again.
  • the resultant bit number and S/N ratio from the encoder 3 are supplied to the controller 4 similarly as described above.
  • next decision step S25 it is determined by the controller 4 whether or not the resultant bit number and S/N ratio meet with standard requirements. If they do not meet with standard requirements as represented by a NO at decision step S25, then the processing proceeds to the next step S26, whereat the parameter of the portion which does not meet with standard requirements is corrected. Then, the processing returns to step S24, wherein the encoder 3 encodes the video data one more time.
  • next step S27 whereat the checking by the user is carried out. That is, the picture processed by the encoder 3 is output and displayed on the video monitor 6.
  • the user corrects a defective portion, if any, while watching the picture displayed on the video monitor 6.
  • the predictive mode and the quantizing parameter are set one more time via the controller 4 in a manual fashion, and the encoder 3 encodes again the video data in accordance with the corrected parameter in step S29. This processing from steps S27 to S29 is repeated until it is determined visually that the picture has no problem.
  • the bit stream output from the encoder 3 is supplied to an apparatus (not shown), thereby being recorded, for example, on a record medium such as a disc or the like.
  • the parameter memory 5 stores all parameters that are adjusted and set as described above. If the parameter is set as described above, then the video data output from the DVTR 1 can be correctly compressed in data amount into image data set and adjusted as described above and then output.
  • the video data input to the encoder 3 from the DVTR 1 are stored in the frame memory 11 thereof.
  • the motion compensator circuit 12 compensates for the video data stored in the frame memory 11 by using the predictive mode and the motion vector input thereto from the parameter memory 5 thereto to generate a predictive picture.
  • Data of the predictive picture whose motion are compensated for is supplied to the DCT circuit 13, in which they are processed in a DCT fashion.
  • the DCT processing expresses a picture not by the pixel level but by the amount of frequency component of a cosine function contained therein. For example, a two-dimensional DCT converts a pixel block of 8 x 8 pixels into a coefficient block of 8 x 8 cosine function components. Accordingly, in a natural picture picked up by a television camera, for example, it is frequently observed that the above coefficient block is presented as a smooth signal. In this case, if the video data are processed in a DCT fashion, the amount of data can be reduced efficiently.
  • the quantizer circuit 14 quantizes the output of the DCT circuit 13 by a predetermined step size in response to the quantizing parameter supplied thereto from the parameter memory 5, then most of the data thus processed in a DCT fashion become zero and a small amount of large coefficient remains. Then, the output of the quantizer circuit 14 is supplied to the variable length coder circuit 15, in which it is scanned in a zigzag fashion to provide a Huffman code (variable length code) having a set of non-zero coefficient and zero-run indicating the number of zeroes continuously provided in front of the non-zero coefficient. A data amount of Huffman code is considerably compressed as compared with the original video data output from the DVTR 1.
  • the output of the quantizer circuit 14 is inverse-quantized by the inverse-quantizer circuit 16.
  • the inverse-quantized data are processed by the inverse DCT circuit 17 in an inverse-DCT fashion and then stored in the frame memory 11. That is. the same data as that quantized by the quantizer circuit 14 and which is output from the variable length coder circuit 15 are stored in the frame memory 11.
  • the motion compensator circuit 12 processes the data in a predetermined manner with reference to the data of the preceding frame stored in the frame memory 11, if necessary.
  • the data thus encoded are read out from the frame memory 11 and supplied to the video monitor 6, thereby making it possible visually to confirm the resultant picture thus processed.
  • the data are coded via a multipath, which can reduce a restriction from a time standpoint and also reduces the amount of hardware needed for encoding.
  • the video coder since the video coder has encoded parameters prepared therein, only a necessary portion need be repeatedly modified, thereby making it possible to effect finer control.

Landscapes

  • Engineering & Computer Science (AREA)
  • Multimedia (AREA)
  • Signal Processing (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Theoretical Computer Science (AREA)
  • Compression Or Coding Systems Of Tv Signals (AREA)
  • Signal Processing For Digital Recording And Reproducing (AREA)
  • Television Signal Processing For Recording (AREA)

Claims (9)

  1. Videocodierer zum Komprimieren der Datenmenge von Eingangsvideodaten und zum Codieren der Eingangsvideodaten, wobei der Videocodierer umfaßt:
    eine Codiereinrichtung (3) zum Codieren (S24) der Eingangsvideodaten gemäß einem Codierparameter, um erste codierte Videodaten bereitzustellen; eine Steuereinrichtung (14) zum Variieren als Antwort auf die ersten codierten Videodaten des Codierparameters, der zur Verarbeitung durch die Codiereinrichtung (3) notwendig ist, um einen variierten Codierparameter zu bilden; und eine Speichereinrichtung (5) zum Speichern des variierten Codierparameters;
       gekennzeichnet durch
       eine Einrichtung zum Speichern (11) der Eingangsvideodaten; und dadurch gekennzeichnet, daß die Codiereinrichtung zumindest einen Teil der Eingangsvideodaten, die in der Speichereinrichtung gespeichert sind und identisch zu den codierten sind, nochmals codiert (S29, S24), um die ersten codierten Videodaten gemäß dem variierten Codierparameter zu erzeugen, um zweite codierte Videodaten bereitzustellen; und wobei der Codierparameter eine Vollbildstrukturinformation umfaßt, die ein Intrarahmen-Codiersystem oder ein Vorhersage-Codiersystem für jedes Vollbild der Eingangsvideodaten angibt.
  2. Codierer nach Anspruch 1, wobei die Codiereinrichtung (3) eine Quantisierungseinrichtung (14) umfaßt, um die Videodaten zu quantisieren, und der Codierparameter einen Quantisierungsparameter umfaßt, um eine Quantisierungscharakteristik der Quantisierungseinrichtung (14) zu steuern.
  3. Codierer nach Anspruch 1 oder 2, wobei der Codierparameter eine Vorhersagemodusinformation umfaßt, die ein Referenzbild auswählt, um eine Differenz von jedem vorher-festgelegten Block eines Vollbilds gemäß einer Vorwärtsvorhersagecodierung, Rückwärtsvorhersagecodierung oder Bidirektional-Vorhersagecodierung zu berechnen.
  4. Codierer nach Anspruch 2, der außerdem eine Bewegungsermittlungseinrichtung (2) umfaßt, um die Bewegung der Videodaten zu ermitteln und bei der die Codiereinrichtung (3) eine Invers-Quantisierungseinrichtung (16), um die Quantisierungsdaten invers-zu-quantisieren, und eine Bewegungskompensationseinrichtung (12) umfaßt, um eine Bewegung der invers-quantisierten Daten zu kompensieren, wobei der Bewegungsvektor verwendet wird, der durch die Bewegungsermittlungseinrichtung (2) ermittelt wird, und der Codierparameter den Bewegungsvektor umfaßt.
  5. Codierer nach Anspruch 4, wobei die Codiereinrichtung (3) eine Einrichtung (13) umfaßt, die der Quantisierungseinrichtung (14) vorhergehend bereitgestellt ist, um die Videodaten in einer diskreten Kosinustransformationsart (DCT) zu verarbeiten, und eine Einrichtung (17), die der Invers-Quantisierungseinrichtung (16) folgt, um die Videodaten in einer inversen DCT-Art zu verarbeiten.
  6. Videocodierverfahren zum Komprimieren der Menge von Eingangsvideodaten und zum Aufzeichnen der Eingangsvideodaten, wobei das Verfahren folgende Schritte umfaßt:
    Wählen eines Codierparameters;
    Speichern des Codierparameters in einer Speichereinrichtung (5);
    Codieren (S24) der Eingangsvideodaten gemäß den Codierparameter, um erste codierte Videodaten bereitzustellen; und
    Variieren als Antwort auf die ersten codierten Videodaten des Codierparameters, der in der Speichereinrichtung (5) gespeichert ist, um einen variierten Codierparameter zu bilden;
       gekennzeichnet durch:
    Speichern der Eingangsvideodaten; und
    nochmaliges Codieren zumindest eines Teils der Eingangsvideodaten, die identisch mit den codierten sind, um die ersten codierten Videodaten gemäß dem variierten Codierparameter zu erzeugen, um zweite codierte Videodaten zu liefern; und wobei der Codierparameter eine Vollbildstrukturinformation umfaßt, welche ein Intravollbild-Codiersystem oder Vorhersage-Codiersystem für jedes Vollbild der Eingangsvideodaten angibt.
  7. Verfahren nach Anspruch 6, wobei der Codierparameter einen Quantisierungsparameter umfaßt, der dazu verwendet wird, eine Quantisierungscharakteristik zu steuern.
  8. Verfahren nach Anspruch 6, wobei der Codierparameter eine Vorhersagemodusinformation umfaßt, die ein Referenzbild auswählt, um eine Differenz eines jeden vorher-festgelegten Blocks eines Vollbilds gemäß dem Vorwärtsvorhersagecodieren, dem Rückwärtsvorhersagecodieren oder dem bidirektionalen Vorhersagecodieren zu berechnen.
  9. Verfahren nach Anspruch 6, wobei der Codierparameter einen Bewegungsvektor zur Bewegungskompensation umfaßt.
EP19920305851 1991-06-27 1992-06-25 Videokoder und Kodierungsverfahren Expired - Lifetime EP0520789B1 (de)

Applications Claiming Priority (6)

Application Number Priority Date Filing Date Title
JP182915/91 1991-06-27
JP18291591 1991-06-27
JP18291591 1991-06-27
JP163647/92 1992-05-29
JP16364792A JP3227674B2 (ja) 1991-06-27 1992-05-29 動画像符号化装置および方法
JP16364792 1992-05-29

Publications (3)

Publication Number Publication Date
EP0520789A2 EP0520789A2 (de) 1992-12-30
EP0520789A3 EP0520789A3 (en) 1993-06-23
EP0520789B1 true EP0520789B1 (de) 2002-01-23

Family

ID=26489031

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19920305851 Expired - Lifetime EP0520789B1 (de) 1991-06-27 1992-06-25 Videokoder und Kodierungsverfahren

Country Status (3)

Country Link
EP (1) EP0520789B1 (de)
JP (1) JP3227674B2 (de)
DE (1) DE69232362T2 (de)

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5640208A (en) * 1991-06-27 1997-06-17 Sony Corporation Video signal encoding in accordance with stored parameters
JP3189861B2 (ja) * 1992-11-13 2001-07-16 ソニー株式会社 動画像符号化装置および方法
CA2137266C (en) 1993-04-09 2003-07-22 Tsuyoshi Oda Picture encoding method, picture encoding apparatus and picture recording medium
US5592226A (en) * 1994-01-26 1997-01-07 Btg Usa Inc. Method and apparatus for video data compression using temporally adaptive motion interpolation
KR960702247A (ko) * 1994-02-15 1996-03-28 이데이 노부유키 화상 신호 부호화 방법 및 장치(Method and device for encoding image signal)
US6100940A (en) * 1998-01-21 2000-08-08 Sarnoff Corporation Apparatus and method for using side information to improve a coding system
JP4428680B2 (ja) 2000-11-06 2010-03-10 パナソニック株式会社 映像信号符号化方法および映像信号符号化装置
CN101578875A (zh) * 2007-01-04 2009-11-11 英国电讯有限公司 利用迭代重新编码的视频信号编码

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0385883A (ja) * 1989-08-30 1991-04-11 Hitachi Denshi Ltd 画像高能率符号化方法
EP0444918A2 (de) * 1990-02-28 1991-09-04 Victor Company Of Japan, Limited Einrichtung zur Datenkompression

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4920426A (en) * 1986-11-10 1990-04-24 Kokusai Denshin Denwa Co., Ltd. Image coding system coding digital image signals by forming a histogram of a coefficient signal sequence to estimate an amount of information
JPH01238388A (ja) * 1988-03-18 1989-09-22 Mitsubishi Electric Corp 画像符号化伝送装置
JPH01241270A (ja) * 1988-03-23 1989-09-26 Hitachi Ltd 画像符号化方式
JPH02172389A (ja) * 1988-12-26 1990-07-03 Victor Co Of Japan Ltd 動画像信号の高能率符号化方式
JPH0744686B2 (ja) * 1989-05-19 1995-05-15 三菱電機株式会社 可変伝送速度画像符号化装置
JP2520306B2 (ja) * 1989-05-24 1996-07-31 三菱電機株式会社 変換符号化装置
EP0401854B1 (de) * 1989-06-09 1997-08-06 Matsushita Electric Industrial Co., Ltd. Einrichtung zur orthogonalen Transformationskodierung
JPH0388489A (ja) * 1989-08-31 1991-04-12 Toshiba Corp 画像符号化方式

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0385883A (ja) * 1989-08-30 1991-04-11 Hitachi Denshi Ltd 画像高能率符号化方法
EP0444918A2 (de) * 1990-02-28 1991-09-04 Victor Company Of Japan, Limited Einrichtung zur Datenkompression

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN vol. 015, no. 261 (E - 1085) 3 July 1991 (1991-07-03) *

Also Published As

Publication number Publication date
JP3227674B2 (ja) 2001-11-12
DE69232362D1 (de) 2002-03-14
EP0520789A2 (de) 1992-12-30
EP0520789A3 (en) 1993-06-23
JPH05183872A (ja) 1993-07-23
DE69232362T2 (de) 2002-09-26

Similar Documents

Publication Publication Date Title
US5640208A (en) Video signal encoding in accordance with stored parameters
EP0597647B1 (de) Bildsignalkodierung
US5719986A (en) Video signal encoding method
US5832121A (en) Method and apparatus for video data compression
US7822118B2 (en) Method and apparatus for control of rate-distortion tradeoff by mode selection in video encoders
US5654759A (en) Methods and apparatus for reducing blockiness in decoded video
US5875003A (en) Apparatus and method for encoding a digital video signal
US7224734B2 (en) Video data encoding apparatus and method for removing a continuous repeat field from the video data
US7050495B2 (en) Video data compression apparatus and method of same
EP1063851B1 (de) Vorrichtung und Verfahren zur Codierung von Bewegtbildsignalen
EP0945023B1 (de) Videokodierung
US7065138B2 (en) Video signal quantizing apparatus and method thereof
JPH11262003A (ja) 一定ビット・レ―トまたは可変ビット・レ―トのためのディジタル・モ―ション・ビデオ・シ―ケンスの２パス符号化方法
JPH07112284B2 (ja) 予測符号化装置及び復号化装置
US20020172282A1 (en) Signal coding apparatus and method, signal recording medium, and signal transmitting method
EP0520789B1 (de) Videokoder und Kodierungsverfahren
JP2000350211A (ja) 動画像符号化方法及び動画像符号化装置
EP1374595B1 (de) Videokodierungsverfahren und -vorrichtung
JP3307143B2 (ja) 画像符号化方法及び画像符号化装置
JP4081727B2 (ja) 画像符号化装置および画像符号化方法、並びに記録装置および記録方法
JP3895414B2 (ja) 映像復号化装置
JP3428332B2 (ja) 画像符号化方法及び装置、並びに画像伝送方法
JP3178233B2 (ja) 画像符号化方法及び画像符号化装置及び光ディスク
JPH0888854A (ja) 動画像符号化方式
JPH0951538A (ja) 画像信号の符号化方法

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A2

Designated state(s): DE FR GB

PUAL Search report despatched

Free format text: ORIGINAL CODE: 0009013

AK Designated contracting states

Kind code of ref document: A3

Designated state(s): DE FR GB

17P Request for examination filed

Effective date: 19931105

17Q First examination report despatched

Effective date: 19950905

APAB Appeal dossier modified

Free format text: ORIGINAL CODE: EPIDOS NOAPE

APAB Appeal dossier modified

Free format text: ORIGINAL CODE: EPIDOS NOAPE

APAD Appeal reference recorded

Free format text: ORIGINAL CODE: EPIDOS REFNE

APCB Communication from the board of appeal sent

Free format text: ORIGINAL CODE: EPIDOS OBAPE

APCB Communication from the board of appeal sent

Free format text: ORIGINAL CODE: EPIDOS OBAPE

APAB Appeal dossier modified

Free format text: ORIGINAL CODE: EPIDOS NOAPE

GRAG Despatch of communication of intention to grant

Free format text: ORIGINAL CODE: EPIDOS AGRA

GRAG Despatch of communication of intention to grant

Free format text: ORIGINAL CODE: EPIDOS AGRA

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

REG Reference to a national code

Ref country code: GB

Ref legal event code: IF02

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): DE FR GB

REF Corresponds to:

Ref document number: 69232362

Country of ref document: DE

Date of ref document: 20020314

ET Fr: translation filed
PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed
APAH Appeal reference modified

Free format text: ORIGINAL CODE: EPIDOSCREFNO

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 20110630

Year of fee payment: 20

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 20110620

Year of fee payment: 20

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 20110622

Year of fee payment: 20

REG Reference to a national code

Ref country code: DE

Ref legal event code: R071

Ref document number: 69232362

Country of ref document: DE

REG Reference to a national code

Ref country code: DE

Ref legal event code: R071

Ref document number: 69232362

Country of ref document: DE

REG Reference to a national code

Ref country code: GB

Ref legal event code: PE20

Expiry date: 20120624

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Free format text: LAPSE BECAUSE OF EXPIRATION OF PROTECTION

Effective date: 20120626

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Free format text: LAPSE BECAUSE OF EXPIRATION OF PROTECTION

Effective date: 20120624